System Programmer Reference › Managing Tape and DASD Resources › Handling Tapes and DASD Resources for Backup and MPC Jobs › Writing to Tapes › Writing to Tapes for CA VM:Archiver Jobs

Writing to Tapes for CA VM:Archiver Jobs

Unlike CA VM:Backup tapes, which can contain only one data set, CA VM:Archiver tapes can contain multiple data sets. Each data set on the tape contains its own tape header labels.

All CA VM:Archiver tapes are owned by the CA VM:Archiver service virtual machine that submitted the job. The tapes have an expiration date of PERM (permanent), which means they do not expire unless the owner of the tapes expires them. The PERM designation protects the tapes from being reused by jobs submitted by user IDs that do not own the tapes. CA VM:Archiver also protect tapes by telling CA VM:Backup which data sets to write, preventing CA VM:Backup from inadvertently overwriting a data set.

CA VM:Archiver always asks CA VM:Backup to write to a specific data set. If the job is canceled while CA VM:Backup is processing it, part of the data set may have been written to the tape; therefore, correct and valid header labels may exist. When CA VM:Archiver submits the next job, it asks CA VM:Backup to write to the same data set that was specified in the canceled job, but when CA VM:Backup encounters the valid tape header labels, it assumes that the entire data set exists.

If the TAPEXPDT configuration file record exists in the VMBACKUP CONFIG file, CA VM:Backup asks permission from the tape operator to overwrite the existing CA VM:Archiver data set. If the tape operator specifies that CA VM:Backup can overwrite the data set, CA VM:Backup writes the new data set. If the TAPEXPDT record does not exist, CA VM:Backup ends the job abnormally.

For a CA VM:Archiver backup job, you can allow CA VM:Backup to overwrite an existing data set if the job still exists in the CA VM:Archiver job queue. The CA VM:Backup job name must match one of the CA VM:Archiver job IDs listed in the CA VM:Archiver job queue; if it does not, do not allow CA VM:Backup to overwrite the data set. For complete information about displaying CA VM:Archiver jobs, see the CA VM:Archiver Operator's Guide. For more information about using CA VM:Backup with CA VM:Archiver, see the CA Mainframe VM Product Manager Product Interface Guide.